It depends how screwed up the alignment of the scope mounting holes on your receiver are for the most part. It is always a good idea if you are putting together a "keeper" rifle that will really shoot. Burris makes rings with inserts that do the same thing by just installing them and allow you to shim the scope if you need to with different size inserts. Signature rings.

I got my ring lapping kit in the mail yesterday and I dragged a couple of rifles out of the safe.I did the rings on my AR and I like how it came out, coolI remove the scope from my 10/22 and I check the alignment and holy crap the alignment is off, way off. I play around with it for a few minutes and there is no way to fix it. That's what I get for cheap rings. My next buy is better rings.

I once lapped the rings on my rifle.... but the lapping removed the anti-corrosion coating for the rings and they rusted like a cheap nail. It doens't hurt performance, but how much it helps is a matter of opinion. YMMV. I would do it again, but only on Aluminum rings.

"God created man, but Sam Colt made them equal." - Unknown"Pistols are pistols and rifles are rifles. Enough said." - Old_Painless